Inhibitory effect of adrenomedullin on L-type calcium currents in guinea-pig ventricular myocytes / 生理学报
Acta Physiologica Sinica
; (6): 479-484, 2002.
Article
in En
| WPRIM
| ID: wpr-318964
Responsible library:
WPRO
ABSTRACT
The effects of adrenomedullin (ADM) on the L-type calcium currents (I(Ca,L)) and the mechanism of the signal transduction process were studied. Enzymatically isolated guinea-pig ventricular myocytes were used to measure ICa,L with whole-cell patch-clamp techniques. ADM at the concentrations of 1-100 nmol/L decreased ICa,L in a dose-dependent manner (P<0.05). ADM22-52) (100 nmol/L), a specific ADM-receptor antagonist, completely abolished the ADM-induced inhibition of ICa,L. Pretreatment of the cells with H-89 (10 micromol/L), a specific PKA inhibitor, did not attenuate the effects of ADM. Intracellular application of 10 micromol/L PKC19-36), a specific PKC inhibitor, prevented the ADM-induced inhibition of the ICa,L, while the specific PKC activator PMA could mimic the effects of ADM on the ICa,L. PMA (1 micromol/L) decreased the ICa,L by 32.26+/-4.20%(P<0.05). These findings indicate that ADM can inhibit the ICa,L in guinea-pig ventricular myocytes, and the inhibition is mediated by the specific ADM-receptor and an activation of protein kinase C.
Full text:
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Index:
WPRIM
Main subject:
Pharmacology
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Protein Kinase C
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Patch-Clamp Techniques
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Calcium Channels, L-Type
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Cell Biology
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Myocytes, Cardiac
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Adrenomedullin
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Guinea Pigs
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Heart Ventricles
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Metabolism
Limits:
Animals
Language:
En
Journal:
Acta Physiologica Sinica
Year:
2002
Type:
Article